Advances in minimally invasive surgical technology could dramatically increase the number of surgeries performed in a minimally invasive manner. Minimally invasive medical techniques are aimed at reducing the amount of extraneous tissue that is damaged during diagnostic or surgical procedures, thereby reducing patient recovery time, discomfort, and deleterious side effects. The average length of a hospital stay for a standard surgery may also be shortened significantly using minimally invasive surgical techniques. Thus, an increased adoption of minimally invasive techniques could save millions of hospital days, and millions of dollars annually in hospital residency costs alone. Patient recovery times, patient discomfort, surgical side effects, and time away from work may also be reduced with minimally invasive surgery.
The most common form of minimally invasive surgery may be endoscopy. Probably the most common form of endoscopy is laparoscopy, which is minimally invasive inspection and surgery inside the abdominal cavity. In standard laparoscopic surgery, a patient""s abdomen is insufflated with gas, and cannula sleeves are passed through small (approximately xc2xd inch) incisions to provide entry ports for laparoscopic surgical instruments. The laparoscopic surgical instruments generally include a laparoscope (for viewing the surgical field) and working tools. The working tools are similar to those used in conventional (open) surgery, except that the working end or end effector of each tool is separated from its handle by an extension tube. As used herein, the term xe2x80x9cend effectorxe2x80x9d means the actual working part of the surgical instrument and can include clamps, graspers, scissors, staplers, and needle holders, for example. To perform surgical procedures, the surgeon passes these working tools or instruments through the cannula sleeves to an internal surgical site and manipulates them from outside the abdomen. The surgeon monitors the procedure by means of a monitor that displays an image of the surgical site taken from the laparoscope. Similar endoscopic techniques are employed in, e.g., arthroscopy, retroperitoneoscopy, pelviscopy, nephroscopy, cystoscopy, cisternoscopy, sinoscopy, hysteroscopy, urethroscopy and the like.
Minimally invasive telesurgical robotic systems are being developed to increase a surgeon""s dexterity when working within an internal surgical site, as well as to allow a surgeon to operate on a patient from a remote location. In a telesurgery system, the surgeon is often provided with an image of the surgical site at a computer workstation. While viewing a three-dimensional image of the surgical site on a suitable viewer or display, the surgeon performs the surgical procedures on the patient by manipulating master input or control devices of the workstation. The master controls the motion of a servomechanically operated surgical instrument. During the surgical procedure, the telesurgical system can provide mechanical actuation and control of a variety of surgical instruments or tools having end effectors such as, e.g., tissue graspers, needle drivers, or the like, that perform various functions for the surgeon, e.g., holding or driving a needle, grasping a blood vessel, or dissecting tissue, or the like, in response to manipulation of the master control devices.
An electrosurgical instrument is an end effector for coagulating ruptured blood vessels or the like. The instrument typically includes an electrode that applies current to living tissue at a surgical site. As the tissue current is conducted through the tissue, the tissue temperature rises, ultimately causing desiccation, cutting, and/or coagulation of the target tissue or vessel. Some cautery instruments include a J-shaped or L-shaped distal hook conveniently configured to snag or capture anatomical tissue such as a blood vessel for cauterization. The J-shaped or L-shaped hook often includes a distal hook portion connected to a substantially straight shank portion. The lateral dimension of the hook portion typically is substantially larger than that of the shank portion. When the cautery hook is passed through a cannula sleeve between the internal surgical site and the outside, the hook portion may get caught at an edge of the cannula sleeve or become stuck in the sleeve, particularly if the hook portion includes a sharp tip. In some cases, the hook portion may even break off when passing through the cannula sleeve.
The present invention is generally directed to robotic surgery methods, devices, and systems. The invention provides a cautery hook that is configured to substantially avoid being caught inside a cannula sleeve and being damaged or broken when the cautery hook is passed through the cannula sleeve.
In accordance with an aspect of the present invention, a cautery hook includes a proximal portion having a proximal end. A shank portion is connected to the proximal portion at a bent knee protruding generally on a front side of the cautery hook. A distal hook portion includes a distal hook tip generally on the front side of the cautery hook. The distal hook portion is connected to the shank portion at an ankle protruding generally on a rear side of the cautery hook opposite from the front side of the cautery hook.
In use, the bent knee, ankle, and distal hook tip are the three most likely locations of contact between the cautery hook and a cannula sleeve when the cautery hook is passed through the cannular sleeve between an internal surgical site and the outside. Each location of contact tends to self-align the cautery hook to allow the hook to pass through the cannula sleeve without getting stuck or damaged.
In some preferred embodiments, a proximal portion line extending generally between the proximal end and the bent knee is angularly spaced from a shank portion line extending generally between the bent knee and the ankle by a bent knee angle generally on the front side of the cautery hook. The bent knee angle is greater than 180xc2x0 and no greater than about 270xc2x0. In a specific embodiment, the bent knee angle is between about 200xc2x0 and about 250xc2x0.
In some preferred embodiments, the distal hook tip coincides with, or is disposed rearward of, a proximal portion plane which extends from the proximal end toward the bent knee and which is generally transverse to a distal hook plane on which the distal hook portion lies.
In some preferred embodiments, a distal hook tip tangent which is generally tangential to the distal hook portion at the distal hook tip is angularly spaced by a master angle from a proximal portion line extending between the proximal end and the bent knee. The master angle is disposed generally on the front side of the cautery hook, and is greater than 90xc2x0, preferably between about 110xc2x0 and about 180xc2x0, and more preferably between about 120xc2x0 and about 150xc2x0.
In a preferred embodiment, a rear support is disposed rearward of the bent knee and extends generally between the proximal end and the ankle.
In another preferred embodiment, the bent knee is spaced from the ankle by a shank portion length and the ankle is spaced from the distal hook tip by a distal hook portion length. The shank portion length is approximately equal to or greater than the distal hook portion length.
In specific embodiments, the distal hook portion is generally linear. The proximal portion, the shank portion, and the distal hook portion are generally planar and generally coplanar with each other. The proximal portion includes an engagement base at the proximal end for coupling the cautery hook to a support shaft.
In accordance with another aspect of the invention, a cautery hook includes a generally linear proximal portion. A generally linear shank portion is connected to the proximal portion at a bent knee. The shank portion is generally coplanar with the proximal portion. A generally linear distal hook portion includes a distal hook tip and is connected to the shank portion at an ankle. The distal hook portion is generally coplanar with the shank portion. The distal hook tip and the bent knee are disposed generally on a front side of the cautery hook and the ankle is disposed generally on a rear side of the cautery hook which is opposite from the front side.
In some preferred embodiment, the distal hook portion is angularly spaced by a master angle from the proximal portion. The master angle is disposed generally on the front side of the cautery hook, and is greater than 90xc2x0.
In accordance with another aspect of the invention, a cautery hook configured to self-align when passed through a cannula sleeve includes a distal hook portion having a distal hook tip disposed generally on a front side of the cautery hook. The cautery hook further includes a proximal end. A protruding portion is formed between the proximal end and the distal hook portion. The protruding portion includes a protruding surface generally on the front side of the cautery hook.
In some preferred embodiments, the bent knee generally coincides with, or protrudes generally forward of, a plane extending between the proximal end and the distal hook tip. The cautery hook further includes an ankle formed between the bent knee and the distal hook tip. The ankle protrudes generally on the rear side of the cautery hook. The protruding portion is formed between a proximal portion extending from the protruding portion to the proximal end and a shank portion extending from the protruding portion to the ankle.
Another aspect of the invention is directed to a system for cauterizing a target tissue in an internal surgical site of a patient body. The system includes a cannula sleeve having a proximal end, a distal end, and a lumen therebetween. The distal end is insertable into the patient body for accessing the internal surgical site through the lumen. A tool extends into the lumen of the cannula sleeve. The tool includes a cautery hook coupled with a shaft by a joint. The cautery hook has a tip supported by a bend so that the tip extends in a forward direction. A surface of the cautery hook is disposed proximally of the bend and extends forward sufficiently that sliding engagement between the proximal hook surface and the lumen of the cannula sleeve aligns the cautery hook with the shaft so as to inhibit interference between the tip and the distal end of the cannula sleeve when the cautery hook moves proximally into the cannula sleeve. The tool may be a robotic tool.
In some preferred embodiments, the bend of the cautery hook is generally planar. The cautery hook is rotatable generally on a plane of rotation relative to the shaft at a pivotal connection with the bend lying generally on the plane of rotation. The proximal hook surface generally coincides with, or extends generally forward of, a plane which is perpendicular to the plane of rotation and extends between the pivotal connection and the tip.